This invention relates to a wireless metropolitan area information communication system, and more particularly to an information communication network utilizing a plurality of high bandwidth wireless links.
Network communications, such as telephony networks and information system networks including those used in the Internet, are typically implemented using land-based communications technologies, which generally use either copper wire or optical fiber. Optical fiber is becoming increasingly popular because of its much higher bandwidth. Due to the physical constraints of fiber optic technology, optical transmissions are typically point-to-point. In this method, each network node (which can be a computer system with communications links to one or more other nodes) transmits to only one node at a time. In some networks, such as Ethernet networks, when the receiving node receives data it examines the destination address in the received data and determines if it is the addressee. If it is, the receiving node keeps and processes that data. If it is not, it retransmits the data to another node which does the same. In other network, this routing may be accomplished by other techniques. For example, time division techniques, such as used in SONET, may be relied upon where information in a particular time slot of a frame is directed to one piece of termination equipment and may be identified and processed accordingly. However, information in a different time slot may be retransmitted to another node. In this manner, the data will eventually reach its destination and be processed. If the network has a linear or ring configuration, each node has only one choice of which node to forward the message to. But if each node has connections to multiple other nodes, each node may contain a routing directory or other aid to help it choose which node to which to forward the message. By judiciously choosing which link to use, each node can help to efficiently route the message to its destination through a complex network with a large number of possible routes.
It is also possible for two systems, telephony, computer, or otherwise, to communicate with each other through radio links, such as through point-to-point radio links using directional microwave antennas. Due to the previous cost of microwave radio technology and licensing constraints, this approach has largely been limited to high capacity dedicated communications between two points rather than common network communications in which traffic is routed through a system of many nodes. With the total cost of the technology dropping, it is becoming economically feasible to implement network links with radio. However, most of the installed systems in these networks use either copper wire or fiberoptic interfaces and, therefore, utilize communications protocols adapted for such media and are not directly compatible with current microwave networks. Moreover, the current point to point systems are not adapted to provide functionality necessary in networking installations, such as the aforementioned routing of information, and therefore do not lend themselves easily to installation as a network element.
In recent years, the FCC has striven to increase competition for local telephone access. At the same time, telecommunications customers"" service requirements have dramatically expanded especially in the area of data networking. New government deregulation has allowed for competitive service providers to enter the marketplace. The present invention is well suited to assist a CLEC (Competitive Local Exchange Carrier), for example, to achieve their service delivery network goals. Beside the increasing need for telephony services, customers have placed increasing demands on data communication infrastructures such as Internet Service Providers (ISP), for reliable data communication, such as wide area networking (WAN), local area networking (LAN), and Internet services. The present invention is also well suited for providing high bandwidth data communication and therefore may be utilized to assist an ISP to achieve their delivery goal.
Both CLECs and ISPs may use the present invention, the preferred embodiment of which is a wireless networks based on 38 GHz microwave technology, for, inter alia, the following reasons: 1) high bandwidth, 2) rapid deployment, and 3) incremental deployment costs.
1) The 38 GHz band as partitioned by the FCC includes 14 channels of 100 MHZ each. Such channels are capable of supporting potentially hundreds of Megabits per second, in contrast to cellular channels which may support a few tens of kilobits per second or T1 lines which support 1.544 Mbps. Thus the use of the 38 GHz frequency bands should provide the much greater subscriber and traffic capacities required by telephony networks or data networks. Of course, spectrum divisions other than those of the 38 GHZ band may be utilized according to the present invention where they may provide sufficient bandwidth to achieve the goals of the present invention.
2) Wireless networks adapted according to the present invention can be deployed in a fraction of the time it takes to deploy in-ground based (copper, fiber, hybrid fiber/coaxial HFC, etc.) systems due to the inherently time consuming processes (permitting, right-of-way resolution, digging etc.) associated with placing cable media in the ground.
3) In addition to rapid to deployment, microwave based service networks of the preferred embodiment of the present invention do not require a massive initial capital investment before any subscribers can get service, which is the case for networks using wire based technologies. The microwave network systems of the preferred embodiment can be built out incrementally, thereby conserving capital while immediately generating revenue.
The preferred embodiment of the present invention further takes advantage of the flexibility afforded by the 38 GHz frequency band licenses granted by the FCC on an area basis, as opposed to other microwave licenses such as in the 23 GHz band, which are allocated as an individual license per point-to-point link. Accordingly, a network coverage plan may be established to provide information communication throughout a metropolitan area utilizing radio links of the present invention, such as shown and described in the above referenced patent application entitled xe2x80x9cSystem and Method for Establishing a Point to Point Radio Systemxe2x80x9d, the disclosure of which is incorporated herein by reference. Thus the 38 GHz frequency band, or similarly regulated frequency bands of radio spectrum, license holders may deploy microwave links at will in their designated service areas nationwide.
Another object of the invention is to provide services at lower entry and deployment costs without the traditional hard-wired network costs associated with cables and trenching.
Another object of the invention is to provide systems that may be deployed rapidly with minimal disruption to the community and the environment.
Another object of the invention is to provide a scaleable architecture incorporating open industry standards which ensures that services and coverage areas can be easily modified and expanded as customer demand warrants.
Another object of the invention is to achieve lower network maintenance, management, and operating costs. Lower ongoing costs are possible given the flexible design options, advanced services, and reduced equipment requirements.
An object of the invention is to provide high speed Internet or other data communication network access. Current Internet access speeds using dial up modem technology or even basic rate ISDN (Integrated Services Digital Network) are inadequate for most commercial users. Alternatives such as DSL (Digital Subscriber Line or Loop) have yet to be deployed in any significant density, while dedicated facilities (leased T1) or Frame Relay service from the (Incumbent Local Exchange Carrier) ILEC (if available) are still prohibitively expensive. The demand is expected to continue to increase as more and more organizations migrate a significant portion of their business transactions onto the Internet and/or other wide area or global data communication network. What is needed is a network that can be deployed quickly that provides high speed connections ranging in the hundreds of Mbps.
Another object of the present invention is to provide for the transport and routing of IP based data communications across a wireless network including TCP, UDP and FTP other protocols.
Another object of the invention is to provide Internet access to end users at user system native speeds and beyond, such as 100 Mbps Ethernet and even Gigabit Ethernet speeds, to provide a network which is seamless and invisible from the user""s vantage point. The data services provided are orientated to work with existing customer equipment (e.g., LANs, WANs and telephony devices) and networking configuration. Data services include LAN transport, Internet access, and virtual private networking.
According to an aspect of a preferred embodiment of the invention, a microwave data network provides high power MMIC""s, integrated antennas, SONET OC-3 and/or Fast Ethernet modems and direct SONET OC-3 and Fast Ethernet fiber interfaces.
According to another aspect of a preferred embodiment of the invention, a microwave data network provides an intelligent Ethernet switching network that transports Ethernet packets between computer networks at different locations using a microwave ring or other topology network. A switch located in the microwave transmitter or receiver unit determines the destination of the packets based on the Ethernet packet address.
According to one aspect of a preferred embodiment of the invention, a network architecture includes distributed processing capability, such as may be provided by Java, C++, or like languages, to provide both the operator and customer with up to the minute information about system and service performance. According to a feature of the invention, new services and capabilities can be rapidly added and downloaded to the network equipment without disruption to the network or the customer. Thus service problems are identified at the outset, while the customer gets xe2x80x9creal timexe2x80x9d feedback on the quality of service obtained plus the opportunity to access and test drive new features, etc.
According to an aspect of a preferred embodiment of the invention, the microwave data network also provides in band management capabilities to address radios by a logical or physical address, such as a MAC address, or an Internet Protocol address. According to another aspect of a preferred embodiment of the invention, the microwave data network provides a system where individual elements of the network have information regarding their performance flow back to a central point to allow management of the population of radios.
According to another aspect of a preferred embodiment of the invention, network information is transmitted throughout the entire radio network using an addressing scheme that includes the physical address or an Internet Protocol address. Accordingly, management of the network may be accomplished from a centralized location with only a single or a few points of presence on the network. Moreover, various ones of the network elements may intercommunicate, such as shown and described in the above referenced patent application entitled xe2x80x9cSystem and Method of Controlling Co-Channel Interference in Point to Point Communicationsxe2x80x9d, the disclosure of which is incorporated herein by reference.
Another object of a preferred embodiment of the invention is to provide a high efficiency and fiber-like quality of service (QoS).
Another object of a preferred embodiment of the invention is to provide a system that can support two-way integrated voice, data, and/or video services over one network architecture with no substantial changes necessary to add new services.
Another object of a preferred embodiment of the invention is to provide an information communication service, such as telephony or data communication services via an ISP, where customers are charged according to the bandwidth actually used and rather than the traditional access rates and tolls.
Another object of a preferred embodiment of the invention is to provide a robust network by providing multiple radio units, duplicate activity collection systems, ISP and points of presence (POPs) may be provided.
According to another aspect of a preferred embodiment of the invention, a microwave data network provides information communication services via point-to-point type and possibly point-to-multipoint type technologies. However, as such a network is envisioned to employ a large population of radio links, with each preferably separately controllable, the population of radios is managed by using a control message routing system utilizing logical and/or physical address of the radios.
According to another aspect of a preferred embodiment of the invention, a microwave data network provides intelligent radio units that can collect, store and transmit data regarding the network and network subscribers. According to another aspect of a preferred embodiment of the invention, an intelligent router or other network element is utilized to identify network subscribers or their associated information communications in order to track the actual bandwidth usage by subscriber to provide information that may be used for network utilization management, allocation, and/or billing of the subscriber.
According to another aspect of a preferred embodiment of the invention, a routing directory that contains the logical and/or physical address for addressable network devices, such as routers located in the wireless network or subscriber equipment coupled to the network, which can be updated to incorporate new addresses and new features that may be down loaded without interrupting network services, such as via a control overhead channel. Such information may be utilized according to the present invention for a number of purposes, such as determining the network resources required for transmission of particular data packets, determining an alternate communication path in case of a fault or to avoid a particularly congested link or portion of the network in transmitting a data packet, etc.
According to another aspect of a preferred embodiment of the invention, a centralized network operations center is coupled to the data network that can manage the complete universe of network radios and/or provide other network services, such as a billing service that is based of the actual amount of bandwidth used by a customer.
According to one aspect of a preferred embodiment of the invention, a data network spans a plurality of nodes with point-to-point type radio link connections adapted to provide networking features of the present invention. The network includes microwave radio stations located at respective nodes, each microwave radio station in radio communication with one or more other microwave radio stations for communicating data between the stations. Also located at each node is a data interface device connected to receive data from the associated microwave radio station. The data interface selectively routes data addressed to the node to the node. Data not addressed to the particular node is combined with data originating at the node and provided to the microwave radio station for transmission to a subsequent node.
According to a feature of a preferred embodiment of the invention, the data interface devices are responsive to a network control channel which is combined with payload data to form the combined data signal using time division multiplexing so that the combined data signal originating at each node is transmitted at the maximum peak data rate of the corresponding microwave radio station.
According to a still further feature of the invention, each of the microwave radio station is in bidirectional communication to support two-way radio communication with a network adjacent microwave radio station for both receiving data from and transmitting data to the respective other microwave radio station. Each of the microwave radio stations may additionally be in radio communication with a previous microwave radio stations for receiving data through the network and in radio communication with a next one of the microwave radio stations for transmitting data through the network. This architecture may further include a network ring topology.
According to another feature of a preferred embodiment of the invention, one of the nodes is a hub of the data network, with other nodes being in radio communication with the hub for transferring data among the nodes.
According to another feature of a preferred embodiment of the invention, one or more of the nodes includes a point-to-multipoint type radio station thereby maintaining radio communication with a plurality of remote nodes.
According to another feature of a preferred embodiment of the invention, one of the nodes may be connected to a remote or second network and to route data between the remote network and the nodes of the subject network.
According to another feature of a preferred embodiment of the invention, the nodes may include a data switch associated with the microwave radio station. The switch responds to address information contained in the received data to selectively route data, thereby providing the node with data addressed to the node. Data not addressed to the node may be processed for retransmission, such as by first combining it with data originating at the node to form the combined data signal.
According to another feature of a preferred embodiment of the invention, the microwave radio stations and data interface devices are mounted together in a common outdoor protective enclosure to thereby simplify instruction and installation.
According to another feature of a preferred embodiment of the invention, the data interfaces are mounted proximate to a directional microwave antenna of each radio station.
According to another aspect of a preferred embodiment of the invention, a network spans a plurality of nodes with radio link connections, ones of the nodes including a terminal device, microwave radio station and data interface device. Each of the microwave radio stations is in radio communication with another for communicating data between the respective nodes. The data interface device is connected to the microwave radio station and operates to forward data (i) to the node terminal or (ii) through and from the node to another node. Thus, the data interface selectively (i) provides portions of the received data to the terminal device and (ii) combines other portions of the received data with data provided by the terminal device to form a combined data signal and provide the combined data signal to the microwave radio station for transmission to another one of the nodes.
According to features of the invention, the terminal may be a computer or telephony equipment or other information communication device, including a network system such as a LAN, which may benefit from network information communications.
According to an aspect of a preferred embodiment of the invention, a method of communicating data between a plurality of network nodes includes substantially four steps. The method provides destination address information corresponding to one of the nodes, modulates a microwave signal with the data and transmits the microwave signal to an intermediate node of the network. The intermediate node receives the microwave signal and, in response to the address information, selectively (i) supplies the data to a terminal, or (ii) forwards the data to another one of the nodes. According to a feature of the method, the message is repeatedly forwarded through nodes of the network until it arrives the node corresponding to the destination address information.
The foregoing has outlined rather broadly the features and technical advantages of the present invention in order that the detailed description of the invention that follows may be better understood. Additional features and advantages of the invention will be described hereinafter which form the subject of the claims of the invention. It should be appreciated by those skilled in the art that the conception and specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present invention. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the invention as set forth in the appended claims.